STUDY OF COMBINED PILE RAFT FOUNDATION ON THE SOIL OF CHAKUPAT AREA

Abstract

Traditional foundations cannot support a structure on weak soil or heavily settling soil. For the purpose of controlling settlement, pile raft foundations are used, with the raft part providing additional capacity at ultimate loading while the piles provide the majority of stiffness under serviceability loads. The utilisation of pile raft foundations in the Chakupat area which lies in the Kathmandu Valley is the subject of this research. The Kathmandu Valley is located in an earthquake-prone area. After the 2015 earthquake, it is suggested to implement a more solid and appropriate building strategy. The ideal alternative for the construction is a piling raft foundation. As more and more tall structures are constructed in Kathmandu, the pile raft foundation has a good chance of success in the valley of Kathmandu. This research explains the idea behind using piles to reduce settlement for raft foundations as well as how pile rafts behave in the soil of Chakupath area. Model tests using the ideas of an embedded pile and a volumetric pile are carried out and compared.This study shows the percentage of weight carried by piles in the CPRF (Combined pile raft foundation) falls as the number of piles is reduced, and increases as pile length is raised. The findings of the model were compared with other papers as well as with analytical calculations for confirmations. A foundation with raft thickness of 0.6 m, pile length of 15 m, diameter of 1 m, and spacing of 4 m is the most suited in Chakupat Area when taking into consideration the examination of the soil structure, settlement, economy, and load sharing. The results show that the CPRF model has a bearing capacity of 573969.62kN, a factor of safety of 4.42, and a stiffness of 433886.01 kN/m. The estimated cost for the selected model was NRs. 76109910.25. The study concluded that CPRF was a feasible foundation for the soil of the Chakupat area, and the proposed model was safe for construction. The findings can provide valuable information for future construction projects in the area, and the cost estimation can aid in budget planning.